EPoS Contribution
EPoS Contribution
Formation of proto-cluster: a virialized structure from gravo-turbulent collapse

Yueh-Ning Lee
CEA, Saclay, FR
The formation of proto-cluster precedes that of the stellar cluster. We discuss the assembly of gas via gravo-turbulent reprocessing inside collapsing molecular clouds, and demonstrate that virial equilibrium is established for the proto-cluster, of which the higher density is favorable for clustered star formation, and that some physical characteristics of the stellar cluster are inherited from the proto- cluster. We performed simulations of proto-cluster formation inside a collapsing molecular cloud and study its energy properties as well as subsequent star formation. We also developed a two-dimensional virial model to account for the quasi-stationary accreting proto-cluster which has non-negligible rotation. Results are compared to observations and the fact that proto-clusters lie on an equilibrium sequence may imply that star formation could be to some extent disentangled from larger scale physics, given an encouraging explanation for the universal IMF.
Caption: Confronting the proto-cluster mass-size relation in observations (Urquhart et al 2014, Fall 2010), simulations, as well as the two- dimensional analytical virial model with varying cloud virial parameter.
P. Hennebelle, CEA, FR
Suggested Session: Cluster Formation